The invention relates to a temperature sensor, a method for measuring a temperature change and a mask inspection apparatus for inspecting a lithography mask with this type of temperature sensor.
For highly accurate determination of the temperature of air for example with milli-Kelvin precision or better, in the prior art platinum temperature sensors are used. These platinum temperature sensors are used, for example, to stabilise the temperature in the region of the mask table of a mask inspection apparatus which is used for the inspection of a lithography mask. However, these platinum temperature sensors drift with several milli-Kelvin per year and react, moreover, to changes to the flow speed of the air surrounding them due to their self-heating. Sensors without any appreciable self-heating, e.g. capacitive length measuring systems, have not until now been able to demonstrate milli-Kelvin measuring accuracy.